Basic grove management – Pruning and biennial bearing

Leandro Ravetti, Modern Olives

2012 AOA National Olive Industry Conference & Trade Exhibition

Olive Physiology

Spring Summer Autumn Winter Spring Summer Autumn Winter

Year n Year n + 1

Shoot Growth

Shoot Growth

Flowering Development Full Bloom & Pollination

Fruit Growth

Pit Hardening Oil Accumulation

Harvest

OLIVE GROWING CYCLE

Biennial Bearing

Involvement of plant regulators and endogenous growth substances in the control of alternate bearing. Lavee, S. Acta Horticulturae 239, 1989

Biennial Bearing

ENVIRONMENT

Growth Rate of vegetative and reproductive

development

Fruit Level of hormonal

signal

Leaf Metabolism Mature buds

Degree of differentiation or

inhibition

Growth regulators Establishment of

equilibrium

Environment

Climatic aspects • Winter chilling. • Damaging frosts. • Adverse conditions at flowering time.

Agronomic aspects • Irrigation. • Fertilisation. • Pest and disease management.

Impact of fruit on biennial bearing

Involvement of plant regulators and endogenous growth substances in the control of alternate bearing. Lavee, S. Acta Horticulturae 239, 1989

Biennial Bearing

Dag, A et al; Timing of fruit removal affects concurrent vegetative growth and subsequent return bloom and yield in olive (Olea europaea L.); Scientia Horticulturae; 2009

Lavee, S et al; Biology and physiology of the olive; World Olive Enciclopedia; IOC; 1996

Fruit Thinning

Hand Thinning • To be completed 3 weeks after full bloom. • Leave an average of 6 olives/30cm of twig. • Very expensive. Chemical Thinning • NAA by time (12 to 18 days AFB). • NAA by fruit size (between 3 and 5 mm). • Concentrations between 120 and 180 ppm. • Urea (Approx. 20 days AFB). • Concentrations between 2% and 6% have been trialed.

Pruning

Pruning

IMPROVE CANOPY EFFICIENCY

• Better light interception.

• Higher leaf to wood ratio.

• Minimal alternant bearing.

• Easier management of the grove.

• Cheaper and more efficient harvesting

operation.

Optimal volume of canopy

The productivity of an olive grove depends on light interception and on canopy volume that is appropriately

illuminated (+30% of radiation).

Training systems

Optimal volume of canopy Pruning

Optimal canopy volume

Juvenile period Adult period

Years

Canopy volume/ha

Optimal volume of canopy

Optimal volume of canopy

Optimal volume of canopy

Early Harvest

Genetics

Typically low alternate bearing • Arbequina. • Arbosana. • Picual. • Pendolino. • Chemlali. Typically high alternate bearing • Coratina. • Barnea. • Frantoio. • Leccino. • Picholine.

Girdling

Girdling

Girdling

Girdling

Girdling

Involvement of plant regulators and endogenous growth substances in the control of alternate bearing. Lavee, S. Acta Horticulturae 239, 1989

Conclusions